Exercise "hello"

1. Build a hello-world program – a program that outputs "Hello, World!".
2. Extra: make it output "Hello, YourUserName!", where YourUserName is your user name (the program must figure it out itself, of course).

Hints:

• Create a folder for the exercise, let's say "prog/hello": mkdir --parents ~/prog/hello. (MacOS users should use short options, I believe).
• Go to your directory: cd ~/prog/hello.
• Create a Makefile with the following content (mind the tabulators!)

  out.txt : hello.exe              # out.txt depends on hello.exe
  	mono hello.exe > out.txt # run hello.exe, send output to out.txt
  
  hello.exe : hello.cs             # hello.exe depends on hello.cs
  	mcs hello.cs             # compile hello.cs into hello.exe
  
  clean:                           # a phoney target, no dependencies
  	rm -f out.txt hello.exe  # remove secondary files
  

  (MacOS users should use short options, I believe).
• Create a file hello.cs with the following content

  class hello{
  	static void Main(){
  		System.Console.Write("hello\n");
  	}
  }
  

• Run make and debug.